In sporting activities, such as football, players wear much protective equipment. For example, a player wears a helmet, to protect the head, and shoulder pads, to protect the shoulders. In spite of this equipment, players continue to be injured. For example, in college football over a seven year period from 1975 to 1982, there were 1005 game related concussions reported.
This lack of protection applies to other sports as well. For example, every year, bicycling causes thousands of emergency room visits and a thousand or so deaths. A common cause of death to a bicycle rider is head and neck injuries.
The mechanisms of these head and neck injuries, whether they are caused by football, bicycling, or some other activity, include hyperextension compression of the neck, axial loading of the neck, hyperflexion of the neck, and helmet enhanced inertia injuries of the head.
One cause of these type of injuries is the fact that the head is allowed to move relative to the rest of the body. When the head sustains an impact (regardless of whether a helmet is being worn) some movement of the head relative to the body is incurred. If the player anticipates the impact, then the player can brace his or her body by tightening neck and shoulder muscles. However, if the impact is unanticipated or if the impact is large, then the player's head may move considerably with respect to the body, causing the player to sustain injury to the neck, head and even shoulders.
In sports, mobility of the head and other body portions is greatly prized. What is needed is an apparatus that protects the head and neck of a human, while permitting the head some degree of mobility.